79 research outputs found
Millimeter emission in photoevaporating disks is determined by early substructures
[abridged]Photoevaporation and dust-trapping are individually considered to
be important mechanisms in the evolution and morphology of protoplanetary
disks. We studied how the presence of early substructures affects the evolution
of the dust distribution and flux in the millimeter continuum of disks that are
undergoing photoevaporative dispersal. We also tested if the predicted
properties resemble those observed in the population of transition disks. We
used the numerical code Dustpy to simulate disk evolution considering gas
accretion, dust growth, dust-trapping at substructures, and mass loss due to
X-ray and EUV (XEUV) photoevaporation and dust entrainment. Then, we compared
how the dust mass and millimeter flux evolve for different disk models. We find
that, during photoevaporative dispersal, disks with primordial substructures
retain more dust and are brighter in the millimeter continuum than disks
without early substructures, regardless of the photoevaporative cavity size.
Once the photoevaporative cavity opens, the estimated fluxes for the disk
models that are initially structured are comparable to those found in the
bright transition disk population (), while
the disk models that are initially smooth have fluxes comparable to the
transition disks from the faint population (), suggesting a link between each model and population. Our models
indicate that the efficiency of the dust trapping determines the millimeter
flux of the disk, while the gas loss due to photoevaporation controls the
formation and expansion of a cavity, decoupling the mechanisms responsible for
each feature. In consequence, even a planet with a mass comparable to Saturn
could trap enough dust to reproduce the millimeter emission of a bright
transition disk, while its cavity size is independently driven by
photoevaporative dispersal.Comment: Accepted for publication in A&
Inflammation-dependent cerebrospinal fluid hypersecretion by the choroid plexus epithelium in posthemorrhagic hydrocephalus
This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordThere is another record in ORE for this publication: http://hdl.handle.net/10871/33419The choroid plexus epithelium (CPE) secretes higher volumes of fluid (cerebrospinal fluid, CSF) than any other epithelium and simultaneously functions as the blood-CSF barrier to gate immune cell entry into the central nervous system. Posthemorrhagic hydrocephalus (PHH), an expansion of the cerebral ventricles due to CSF accumulation following intraventricular hemorrhage (IVH), is a common disease usually treated by suboptimal CSF shunting techniques. PHH is classically attributed to primary impairments in CSF reabsorption, but little experimental evidence supports this concept. In contrast, the potential contribution of CSF secretion to PHH has received little attention. In a rat model of PHH, we demonstrate that IVH causes a Toll-like receptor 4 (TLR4)- and NF-κB-dependent inflammatory response in the CPE that is associated with a ∼3-fold increase in bumetanide-sensitive CSF secretion. IVH-induced hypersecretion of CSF is mediated by TLR4-dependent activation of the Ste20-type stress kinase SPAK, which binds, phosphorylates, and stimulates the NKCC1 co-transporter at the CPE apical membrane. Genetic depletion of TLR4 or SPAK normalizes hyperactive CSF secretion rates and reduces PHH symptoms, as does treatment with drugs that antagonize TLR4-NF-κB signaling or the SPAK-NKCC1 co-transporter complex. These data uncover a previously unrecognized contribution of CSF hypersecretion to the pathogenesis of PHH, demonstrate a new role for TLRs in regulation of the internal brain milieu, and identify a kinase-regulated mechanism of CSF secretion that could be targeted by repurposed US Food and Drug Administration (FDA)-approved drugs to treat hydrocephalus.We thank D.R. Alessi (Dundee) and R.P. Lifton (Rockefeller) for their support. K.T.K. is supported by the March of Dimes Basil O'Connor Award, a Simons Foundation SFARI Grant, the Hydrocephalus Association Innovator Award, and the NIH (4K12NS080223-05). J.M.S. is supported by the National Institute of Neurological Disorders and Stroke (NINDS) (NS060801; NS061808) and the US Department of Veterans Affairs (1BX002889); R.M. is supported by the Howard Hughes Medical Institute
Development and Evaluation of a New Lateral Flow Immunoassay for Serodiagnosis of Human Fasciolosis
Fasciolosis is an important plant-borne trematode zoonosis. This disease is of both clinical and veterinary relevance and, according to the WHO, is considered a re-emerging disease that is spreading around the world. Fasciolosis has a serious impact on health because of the large size of the parasite and the effects of the parasite in down-regulating the host immune response. Human fasciolosis can be distinguished by an acute phase, in which the parasite migrates through different tissues, and a chronic phase in which it invades the bile ducts. Here we describe the development of a rapid, simple and inexpensive immunochromatographic diagnostic method, based on the use of a recombinant cathepsin L1 protein, which performs better than other more complex indirect methods, providing similar specificity and higher sensitivity. The simplicity of the method represents a great advantage for the intervention systems applied in different endemic areas by WHO, such as passive case finding (e.g. Vietnam) and selective treatment (e.g. Egypt). Because of its characteristics, the system can be applied to both phases of the disease, and in holo, meso and hyperendemic areas where point-of-care testing is required
Desarrollo tecnológico en ingeniería automotriz
El proceso de investigación y desarrollo tecnológico está directamente relacionado con una adecuada metodología de procesos industriales, que cada vez son más exigentes en competitividad, eficiencia energética y de normativas ambientales. Este libro contempla resultados de un proceso de investigación y desarrollo de nuevas técnicas aplicadas en el campo de la Ingeniería Automotriz desde cuatro aristas: eficiencia energética y contaminación ambiental, planificación del transporte, ingeniería del mantenimiento aplicada al transporte y desagregación tecnológica.
Este libro conmemora 20 años de formación universitaria salesiana en el sector de transporte y recoge las experiencias y resultados obtenidos asociados con el desarrollo tecnológico en ingeniería automotriz. Para lograr este objetivo, se ha convocado a la comunidad científica, académica y profesionales de la industria automotriz a participar en la publicación. Cada capítulo fue sometido a revisión, evaluación y aprobación por un comité científico altamente calificado, proveniente de seis países: Colombia, Ecuador, España, Guinea Ecuatorial, México y Venezuela.
Este trabajo ha sido posible gracias al gran apoyo de la Universidad Politécnica Salesiana (UPS sede Cuenca), Ecuador y Universidad de Los Andes (ULA)
Gut content analysis of Anadara tuberculosa (Sowerby, 1833) throu
The gut content of 30 wild specimens of Anadara tuberculosa collected in April, May, June and October 2000 in the Pacific coast of the Baja California Peninsula was analyzed. Histological sections of the gut were obtained. One thousand and two structures were found, 917 corresponding to diatoms (91.5%), 88.2% of which corresponded to the benthic diatom Paralia sulcata (45.3%) and the planktonic diatoms Thalassiosira spp. (42.9%), Thalasionema nitzchioides (2.7%). The diatom Diploneis sp. (1.2%) and the silicoflagellate Dictyocha spp. (1.6%) were less abundant. Additionally, 85 structures were found (8.5%) consisting of bivalve eggs (1.8%), sponge spicules (0.4%) and unidentified material (6.3%). From these findings, it is concluded that, for this bivalve, gut histological sections represent a new alternative for studying the gut content, facilitating the identification of phytoplankton cells through the observation of diatoms frustules
Thelaziosis in Humans, a Zoonotic Infection, Spain, 2011
After Thelazia callipaeda infection in dogs and cats were reported in Spain, a human case of thelaziosis in this country was reported, suggesting zoonotic transmission. The active reproductive status of this nematode in situ indicates
that humans are competent hosts for this parasite
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